1. Field of the Invention
The present invention relates in general to burn-in processes for computers. More particularly, the present invention relates to a burn-in process for computers whereby power is cycled to the computer.
2. Description of Related Technology
The term "burn-in" is a common and well-known term in the electronics industry which refers to a testing method performed on electrical and electronic components, subassemblies and complete systems thereof. The burn-in process detects early failures, and allows manufacturers to replace or repair units which have failed under constant exposure to predetermined environmental or operational stresses, thereby ensuring the reliability of the circuits and systems once they have been placed in use with the customers.
The process of power cycling electronic components and circuits during the burn-in phase is well-known in the industry. However, in the computer manufacturing industry, there has been no method or apparatus which power cycles the entire computer during the burn-in phase while diagnostically testing various components, systems and/or interfaces within the computer between successive power-off cycles. Such power cycling can detect many types of early failures associated with the power-up and power-down of the computers. Such failures include, but are not limited to, for example, the failure of the basic input/output system (BIOS) to reset during the power-up phase of the computer, which can result in, for example, no video signal being sent to the video monitor by the computer. Other failures include the hard drive not booting upon power-up of the computer, the floppy drive not booting upon power-up of the computer, and an incorrect memory quantity reporting after a power-on self-test (POST) of the computer. All of these failures relate to the BIOS resetting to default values or the BIOS code being corrupted. The BIOS code is a program stored in either a flash ROM or EEPROM of a computer motherboard or its peripherals, such as video adapters, hard drives, zip drives, cd-roms, etc. BIOS is a program which configures the computer system or peripherals to accept specified inputs and outputs from and to other integrated devices (peripheral devices). Upon initial power-up of the computer, it is the BIOS which provides system parameters, e.g., configuration parameters of the hard disk, etc., and allows the computer to "boot-up" a particular operating system, such as Windows 95.RTM.. Occasionally, the BIOS code is corrupted upon power-up of the computer such that the system parameter settings reset to default values which are incorrect for a particular computer configuration. When this occurs, the computer will not operate properly because the subsystems of the computer are unable to communicate properly with each other and to peripheral devices connected to the computer. This defect may be discovered during power cycling of the computer. Other defects which may be detected by power cycling the computer are a defective power supply and defective connections between the various circuits and components of the computer. By rapidly heating and cooling the components within a computer, power cycling can detect faulty circuit and/or components which do not perform within specified tolerances as a result of this rapid heating and cooling. Typically, such faulty circuits or components cause current fluctuations which can damage the computer or detrimentally effects its performance.
In the prior art, there are apparatuses and methods for automatically testing and power cycling computers. However, these prior art systems and methods do not operate in conjunction with a diagnostic program embedded within the computer to fully test various components, systems and/or interfaces within the computer while power cycling the computer in a simple, less expensive and elegant manner. For example, Mallory et al., U.S. Pat. No. 5,353,240, which is incorporated herein by reference, discloses a test apparatus and method for automatically testing computing equipment.
The test apparatus disclosed by Mallory et al., comprises a switch for switching power to a computer and also includes a complicated testing circuit coupled to the switch for testing whether the computer has turned on successfully. However this test apparatus does not operate in conjunction with a diagnostics software program as would be required to test various components, subsystems and/or interfaces within the computer. Instead, the test apparatus of Mallory et al., has a microprocessor based testing circuit which receives signals from the computer via the keyboard port of the computer.
The microprocessor of the test circuit disclosed by Mallory et al. has a memory for storing a time signal received from the computer. In addition, the testing circuit has the ability to receive a condition signal from the computer which indicates whether the computer has successfully restarted following the passage of a period of time. This condition signal also indicates whether testing on the computer is currently in progress, whether the computer needs attention, or whether the computer has successfully rebooted, failed or timed out.
Prior art test apparatus, such as that described above, do not provide thorough diagnostic testing of the various systems and components of a computer during rigorous power cycling of the computer. For example, Mallory et al., does not disclose any type of software diagnostics program, embedded within the computer, which cooperates with the power-cycling apparatus in order to test and power cycle the computer. Rather, Mallory et. al., discloses a complex microprocessor based testing apparatus and power cycling circuit which can only test whether the computer has successfully restarted.
Systems such as that disclosed by Mallory et al. have not met the needs of the rapidly growing computer manufacturing industry which include the need to test for conditions such as improper resetting of the computer's BIOS code, or corruption of the BIOS code, or faulty circuits on the motherboard which can only be detected by a diagnostics program operating in conjunction with the power cycling of the computer.
Because it would be extremely tedious, and would consume human resources, to manually turn a computer on and off while running various diagnostic tests via a software program embedded in the computer during power cycling, a method and apparatus are needed which can automatically power cycle the computer and successively run diagnostics tests on the computer in order to detect various defects within the computer at an early stage after the manufacturing process.